Stroke and major bleeding risk in elderly patients aged ≥75 years with atrial fibrillation: the Loire Valley atrial fibrillation project.

Abstract

Atrial fibrillation (AF) is increasingly prevalent in the elderly, but such patients tend to be under-represented in clinical trials. Increasing age confers a higher risk of stroke and bleeding when antithrombotic therapy is used. We examined risk factors for stroke and bleeding among elderly (age, >75 years) patients within a real world hospitalized cohort from the Loire Valley AF project. We identified elderly (age, >75 years) patients with AF, assessed their risk factors, and followed up for stroke, thromboembolism, death, or major bleeding. The effect of vitamin K antagonist (VKA) use on these end points was assessed. We studied 8962 patients with AF, and we identified 4130 elderly (age, ≥75 years) patients. Using Kaplan-Meier analyses, event rates of death, stroke/thromboembolism, the composite of stroke/thromboembolism/death, and major bleeding increased with increasing age. For mortality, VKA-treated patients did better than non-VKA-treated patients. The risk of death and stroke/thromboembolism/death increased with increasing age. The risk of major bleeding did not increase with increasing age strata. VKA treatment was associated with lower mortality in those aged <75 years (adjusted hazard ratio [HR], 0.57; 95% confidence interval [CI], 0.45-0.72), and the effect size was maintained with increasing age strata (Pint=0.67). For stroke/thromboembolism/death, VKA also has a significant benefit in those aged <75 years (adjusted HR, 0.69; [0.57-0.83]), and the effect size was maintained with increasing age strata (Pint=0.58). For major bleeding, there was no statistically significant difference between age strata (Pint=0.67). In elderly patients, age and previous stroke emerged as the main predictors of stroke and thromboembolism. Renal impairment and VKA use were predictors of major bleeding. Elderly patients with AF have a higher risk of stroke and bleeding, but the benefits of VKA therapy for stroke/thromboembolism or mortality were present regardless of increasing age.